Hypoponera traegaordhi (Santschi)

Bolton, B. & Fisher, B. L., 2011, Taxonomy of Afrotropical and West Palaearctic ants of the ponerine genus Hypoponera Santschi (Hymenoptera: Formicidae)., Zootaxa 2843, pp. 1-118 : 108

Hypoponera traegaordhi (Santschi)

Ponera traegaordhi Santschi , 1914c: 6. Syntype worker, SOUTH AFRICA: Natal, Pietermaritzburg, 21.iii.05 (I. Trågärdh) (NHMB) [examined]. [Combination in Ponera (Hypoponera) : Santschi, 1938: 79; in Hypoponera : Bolton, 1995: 216.]

WORKER. Measurements: HL 0.55, HW 0.43, HS 0.490, SL 0.36, PrW 0.33, WL 0.70, HFL 0.34, PeNL 0.14, PeH 0.30, PeNW 0.22, PeS 0.220. Indices: CI 78, SI 84, PeNI 67, LPeI 47, DPeI 157.

Eyes absent. Apex of scape, when laid straight back from its insertion, conspicuously fails to reach the mid-point of the posterior margin in full-face view; SL/HL 0.65. Gap between apex of scape and midpoint of margin 0.22 × SL, about the apical width of the scape. Cephalic dorsum finely and quite superficially reticulate-punctate. Punctate sculpture on dorsum of mesosoma faint and superficial, the punctures smaller and much less dense than on the head. Mesonotal-mesopleural suture absent. Mesopleuron smooth, its anterior margin bluntly angulate behind the anterior coxa. Metanotal groove entirely absent from dorsum. Dorsa of mesonotum and propodeum with scattered, minute punctures on a glossy surface. Declivity of propodeum separated from sides by blunt angles, not sharply marginate or carinate. Posterior surface of petiole node with a distinct series of short, cuticular ridges that radiate upward from the posterior peduncle across its width. The cuticular ridges terminate dorsally in a darkly coloured, arched transverse rim or carina, much more darkly coloured than the surrounding cuticle. This transverse rim marks the upper boundary of a transverse depression, within which the cuticular ridges are located. With petiole node in profile the anterior and posterior faces are extremely feebly convergent dorsally. Subpetiolar process with an obliquely descending anterior face, a blunt ventral angle and a straight ventral surface that slopes upwards posteriorly. Base of cinctus of second gastral tergite with a continuous row of cross-ribs. Maximum width of first gastral tergite in dorsal view is distinctly less than the width of the second tergite at its midlength. Midline length of second gastral posttergite, from posterior margin of cinctus to apex, is distinctly less than the maximum width of the segment. Disc of second gastral tergite with minute punctures that are relatively close-packed but separated by smooth cuticle, the sclerite appears vaguely microreticulate only in places. First gastral tergite in profile with very short standing setae that project above the level of the decumbent pubescence. Full adult colour yellow.

H. traegaordhi appears to be very close to the Ethiopian species exigua . The two uniquely share the presence of a transverse impression that contains cuticular ridges at the base of the posterior surface of the petiole node. These two are separated by the characters given in the key and under exigua . H. traegaordhi also appears to be related to the South African species natalensis and austra , which also possess a transverse impression on the posterior surface of the petiole node, but these lack cuticular ridges within the impression, the scapes are longer and when laid back reach much closer to the midpoint of the posterior margin, the subpetiolar process has a shallow lobe with a defined ventral angle, the disc of the second gastral tergite is more obviously microreticulate, and a weak eye-spot is usually present, though it is generally no more than a tiny featureless disc. The presence of radiating cuticular ridges on the posterior surface of the petiole brings traegaordhi out in the key together with jeanneli , hebes and their relatives, but this appears to be a convergent development because none of these has a transverse impression on the posterior surface of the petiole.

In the original description Santschi says that traegaordhi has “ eyes indistinct, reduced to a small point in the anterior quarter ”. In the surviving syntype no trace of an eye can be seen and it is suspected that Santschi misinterpreted part of the punctate sculpture.